430 Cup rear diffuser (parts involved for swap)

[MrP_]

No those parts are for the v6 cup not the 410/430 style diffuser

You need the diffuser: B138U0212F

Part 14a on here

And the grill, either B138U0272F if you don't want the hole for towing strap (as per 410), or B138U0271F if you do want the hole for towing strap (as per 430)

Part 35 on here

Then 4x M6 spire nuts, M6*18 button head bolts (4), 4x M6 washers. If you haven't already, replace all the other fixings for stainless.

[PJ]

Very helpful, such a big loss ordering the incorrect stuff..

This should be it right? 

[Karls]

Yes. If you refer back to the first post on this thread the part numbers are confirmed there.

[mikey k]

Liking the idea of DIYing this on my 350 Sport.

Does the rubber trim protect the back edges of the diffuser? ie is it visible on the fins and edge?

[Sharky]

This thread has been very useful. The parts are on back order with Lotus though.

 

Out of interest, for those who added the tow loop, did you use the 430 specific tow bracket?

[MrP_]

@Sharky yes the 430 cup bracket puts the loop out horizontal, the v6Cup bracket holds the loop on its side. The 430cup bracket is also cheaper

[MrD]

Bringing this back to life:)

Can I pls double check that only the rear diffuser assemply and grille are required to do the swap over and not the diffuser finisher?

As it stands, the diffuser assemply on early cars is attached to the grille, am i right to think that the 410/430 grille can be attached to the existing early finisher and from there i can use the existing fittings to fit the late difusser assemply?

Later prices are £113.97 for the grille and £405.81 for the diffuser, £624 all in. Which is not terrible.

Thanks and happy new Year:)

  

 

[Diablos-666]

I’m looking to do the same thing to my v6s - really like the 430 cup diffuser 

[MrD]

Just to update this, it seems that the early CUP cars would also need a different bracket for the toe strap. That is because the strap is vertical on the V6 CUP but orizontal on the later ones. Still not sure whether the mounting holes are the same, I assume they are. Deroure has no price currently but says 'contact us'.

Also, can anyone please confirm whether the 380 CUP diffuser is the same as the 430 CUP? Going from the pics in original post, the 380 CUP setup looks better than 430 to my eyes, the honeycomb grille is smaller and matches the rest of my car whilst the actual diffuser is pointing slightly upwards.

 

 

 

[Kristof Thys]

On 30/12/2021 at 13:12, MrD said:

Bringing this back to life:)

Can I pls double check that only the rear diffuser assemply and grille are required to do the swap over and not the diffuser finisher?

As it stands, the diffuser assemply on early cars is attached to the grille, am i right to think that the 410/430 grille can be attached to the existing early finisher and from there i can use the existing fittings to fit the late difusser assemply?

Later prices are £113.97 for the grille and £405.81 for the diffuser, £624 all in. Which is not terrible.

Thanks and happy new Year:)

  

 

Like per my post: you need the grille and the diffuser; not the finisher. 

 

The 380 cup diffuser is different to the 430 cup one.  I fitted the 430 cup one.

[MrD]

Thanks Kristof, as mentioned i wanted to double check prior to starting ordering parts. As per my comment and for info for future members, early cup car owners would also need the tow strap bracket so it's 3 parts in total, one rarer than the other it seems..

[Diablos-666]

Managed to fit the 430 diffuser this weekend (with some help from a mate)

The hardest part was swapping the vertical tow strap bracket for the horizontal bracket. 

Managed to pick up the diffuser for £350 and the grille for about £115. The bracket was £30 so costs were really reasonable considering it was all OEM.

 

[Sharky]

I was really pleased with the results after doing this mod. One thing I found was that of the four mounting bolts that are not the rear grill fixing or connection to the under tray, the forward most holes on each side didn't line up with the existing hangers. Did anyone else find this and what solution did you use? I've noticed on some pictures from other cars that the forward holes look to have been slotted. 
 

[Diablos-666]

Which holes are you referring to?

 

[Sharky]

The ones here. They pick up on a bracket that supports the 'pointy' ends of the rear valance that houses the reversing sensors. If these were direct fit for everyone I've done something wrong 🙈

 

 

[Diablos-666]

I don’t remember there being a major issue, I did have a mate help so it was easier to align everything. 
we just loosely bolted everything together, lined up and tightened. 
 

[JackandCoke]

@Sharky I found I needed to tweak the two rear hangers to get the diffuser to sit right, then put all the fixings in finger tight then start from the rear when tightening it all back up again which drew the rear brackets into place, the brackets are quite thin so form easily to the different whole locations.

I haven't purchased a rear finisher yet as I've got the early Cup tow strap, I've just made some temporary brackets which I may just change out for adjustable diffuser rods.

[Sharky]

Looks like I need to revisit this. Thanks for the feedback 👍🏼

[MrD]

On 30/01/2022 at 19:56, Diablos-666 said:

Managed to fit the 430 diffuser this weekend (with some help from a mate)

The hardest part was swapping the vertical tow strap bracket for the horizontal bracket. 

Managed to pick up the diffuser for £350 and the grille for about £115. The bracket was £30 so costs were really reasonable considering it was all OEM.

 

Second that. What on earth was lotus thinking by not having the captive nuts fixed? There is literally no space there and trying to align the bracket with the bolts was impossible, especially from the side of the heat shield. I spent 2 hours just for 4 bolts. Insane.

[Diablos-666]

I think we spent about 3/4 hours getting this done and by far the longest part was fitting the new tow strap bracket.

Stupid design! Obviously it would have been easier if we dropped the exhaust but we didn’t want to go through all that just for 4 bolts - for something I hope I never have to use. 
 

 

[Exx]

I asked komotec to do the swap and they told me i need diffusor, grill and ducts .. what would be that duct ?

[Diablos-666]

I think the ducts they are referring are on the existing diffuser which you just transfer over. 
 

 

[Exx]

Got this answer : The ducts are the plastic parts that you need for the airflow. You need two of them (35€/each)